# Longitudinal Associations of Sedentary Behavior and Physical Activity With Sleep Duration and Quality in Individuals Living With and Beyond Colorectal Cancer

## TL;DR

This study explores how sitting, standing, and physical activity affect sleep in colorectal cancer survivors over five years.

## Contribution

It is the first to examine longitudinal associations between sedentary behavior, standing, and physical activity with sleep outcomes in CRC survivors.

## Key findings

- More sedentary behavior is linked to shorter sleep duration.
- Standing more improves sleep quality and reduces insomnia symptoms.
- Higher intensity physical activity reduces insomnia symptoms.

## Abstract

Poor sleep quality and disturbances are common in colorectal cancer (CRC) survivors. However, the impact of sedentary behavior, standing, and physical activity on sleep duration and quality remains under-explored in this population. Therefore, this study examined longitudinal associations of sedentary behavior, standing, and physical activity with sleep outcomes up to 5 years post-treatment.

A prospective cohort study was conducted among 401 survivors of stage I-III CRC, with repeated measures up to 60 months post-treatment. Thigh-worn accelerometers were used to measure sedentary time (per 2h/day), standing (per 1h/day), and various levels of physical activity (per 1h/day). Sleep duration (h/night) and variability (0%–100%; higher variability equals more sleep disruption) were determined from self-reported sleep times. Sleep quality and insomnia symptoms were assessed using the PSQI and EORTC questionnaires, respectively, where higher scores indicated worsened symptoms. Longitudinal associations were analyzed using confounder-adjusted linear mixed models.

Total mean sedentary time was 10.3 ± 1.8 h/day, mean standing time was 2.9 ± 1.2 h/day, mean total physical activity was 1.5 ± 0.6 h/day, and mean sleep duration was 8.7 ± 1.0 h/night at 6 weeks post-treatment. More sedentary behavior was longitudinally associated with a shorter sleep duration (β = −0.28; 95%CI = −0.35, −0.21). More standing was associated with a shorter sleep duration (β = −0.21; 95%CI = −0.25, −0.16), higher sleep variability (β = 0.29%; 95%CI = 0.03, 0.55), improved sleep quality (β = −0.24; 95%CI = −0.43, −0.04), and reduced insomnia symptoms (β = −2.00; 95%CI = −3.27, −0.72). More total physical activity was associated with a shorter sleep duration (β = −0.31; 95%CI = −0.41, −0.21) and higher sleep variability (β = 0.59%; 95%CI = 0.11, 1.10). More moderate-to-vigorous physical activity was associated with a shorter sleep duration (β = −0.04; 95%CI = −0.07, −0.00) and reduced insomnia symptoms (β = −1.74; 95%CI = −2.69, −0.79).

Our findings suggest that physical (in)activity and standing are relevant for sleep-related symptoms in CRC survivors. Future studies should examine whether substituting sedentary behavior with standing and/or physical activity may alleviate sleep-related symptoms in CRC survivors.

How sitting and physical activity can affect sleep in people living with and beyond colorectal cancer: Introduction: Poor sleep quality is common among people living with and beyond colorectal cancer. However, the effect of sitting, standing, and physical activity on sleep duration and quality has not been studied extensively. Therefore, this study investigated how sitting and physical activity affect sleep in people living with and beyond colorectal cancer over a period of 5 years after their treatment ended. Methods: 401 survivors of colorectal cancer were included within this study. These survivors were measured repeatedly over a period of 5 years. We used a device worn on the thigh to measure how much time people spent sitting, standing, and moving. Additionally, we measured how many hours people spent sleeping, how their sleep quality was, and whether people had trouble falling asleep using diaries and questionnaires. Results: After treatment, people who spent more time sitting, standing, and being physically active had a shorter sleep duration. In addition, people who spent more time standing had improved sleep quality and less trouble falling asleep. We also observed that people who spent time moving at a higher intensity experienced less trouble falling asleep. Conclusion: These results indicate that survivors who stand and move more experience less sleep problems and have less trouble falling asleep. Therefore, there may be a critical role for these behaviours in improving sleep in survivors of colorectal cancer. More research is needed to investigate the effects of substituting sitting by more time standing and being physically active.